smeg, the mimicking thing is great fun to use on others and is great when people watching. do you pee more in the cold because the capilliaries and all that constrict and so the blood goes through the kidneys quicker? i.e. less blood on the outside and more on the inside as it were. why not tip the bucket over them....
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 Kate, Needing to pee more in the cold is very closely related to the effect I described above in response to hot temperatures. Just as the body directs blood to the vessels near the skin surface when hot, it withdraws blood from the periphery when cold. Guess what… this one’s called peripheral vasoconstriction. This is good for survival as it reduces the skin surface temperature (leading to lower heat loss) and increases the effective insulation thickness between the viscera (body core) and periphery (extremities, skin surface). However, there are consequences… The effect of circulating the same volume of blood around only the larger internal blood vessels is to push up the blood pressure. The actual mechanism of what happens next is somewhat disputed, but seems to be due to a combination of effects on the kidneys. There’s the physical effect on the rate of osmosis through the kidneys (glomerular filtration) – higher pressure means that more water is ‘squeezed’ through the membranes and ends up as urine in the bladder. And there’s the hormonal effect – the kidneys sense the increased blood pressure and, through a complex pathway of biochemistry, the amount of anti-diuretic hormone (ADH) is reduced. ADH is what the body uses to create concentrated (dark) urine – suppressing ADH means the opposite… lots of dilute (clear) urine is produced. This can, unfortunately, give a false sense of security. I have often mentioned the importance of keeping track of your urine colour to stay hydrated – but the increased urine production due to cold exposure (known as cold diuresis) can mask underlying dehydration. This is one of the many reasons why it is important to keep drinking in cold environments, even if this does mean regular pee stops! And it can lead to electrolyte loses so your food needs to contain some salt or you’ll need an isotonic drink (which is easy to make at home). Oh… and all this comes with my standard disclaimer! I am not a medical professional – just an enthusiastic amateur. So take my advice with a pinch of salt (sic!).John
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Parky, I should learn to say things as concisely as you! Looks like our posts crossed in the ether... John
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CP, you're right - it is lukewarm water (I am told). Ice water would wake the victim up I would expect... if not it could do some serious damage after only a short time so definitely not recommended.
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 John, are you recommending that OMers play practical jokes on each other? I'm shocked!!!  Thanks Parky and John by the way for your responses to my urinary query!
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but your reply was so much more interesting though john! i learnt something about continuing to drink when it's cold.
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I am not so much advocating the prank as advising on how it should be done properly . Parky, as I said - there are many good reasons to continue to drink in the cold. If it is very cold then the air holds little moisture and you inevitably lose more vapour from the lungs when you breathe. They have to stay damp to keep the alveoli working properly. Then of course, there's the fact that our modern clothing does such a good job of removing perspiration that we are often not aware that we are overheating in the cold. This leads to increased sweat rates, increased energy expenditure and increased dehydration. The decreasing blood volume from increased urination can also up the risk of frost bite or non-freezing cold injury. Overall, it is good practice to drink regularly in the cold and to learn to remove extra insulation before you get too hot. Asides from the basic improvement to your comfort, it can help you stay safe if you end up being pushed to your limits.
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 I was over visiting my parents today and mentioned the debate about lukewarm water versus icecold water for making someone pee themselves. My father, being a good scientist, said " lets find out, your mothers asleep upstairs." I can now say that it has been proven beyond all doubt, icecold water is the winner!
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They must be very proud, Mike! I am curious... did you try both methods to be sure which worked best?
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The lukewarm just stopped her snoring. It was the icecold that increased the laundry.
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 Probably scared her to the point of wetting herself!
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Should have thought just seeing her son would have been enough to scare her that much!
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 HA HA, the Missus has just gone to bed. I will wait a few minutes! Ha ha ha ha etc. - Evil Laugh!
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Why did early man lose most of the hair on their bodies?
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Because man invented Paramo and no longer needed the natural insulation
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 Why did early man lose most of the hair on their bodies? So are you saying that the less hirsute we are, the further up the evolutionary scale we are? [thinks about hairy men and not-hairy women] 
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women are just as hairy. we don't like to mention it unless the medical insurance covers the type of injury that results. <hides> if bald men don't live as long as those with hair, will a hair transplant make them live longer? conversely, will shaving your head reduce your life expectancy?
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if bald men don't live as long as those with hair... I missed that...who said that?
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Gregor, the answer is "if there is such a time, it is longer than 20 minutes", as that's roughly how long I was in the pool for before emerging and noticing one from the day before by my navel Peter, are you sure the tick didn't swim to the surface, took a fresh breath of air and dove back to your navel?
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